Clamping device for disk-shaped memory sheets

Abstract

Apparatus to guide and to clamp a memory sheet (recording media) for use.

What is claimed is: 
     
       1. A centering and clamping device for disk-shaped memory sheets having circular holes in the center thereof, said device comprising: a frame having side walls; a frusto-conical member rotatable on one side wall; a cup-shaped member mounted on another side wall having a recess facing said frusto-conical member concentric therewith, said cup-shaped member having a rim around said recess, the diameter of said frusto-conical member growing smaller in the direction of said cup-shaped member, said frusto-conical member being movable in opposite directions through and out of a memory sheet hole into and out of said recess to center the memory sheet, said frusto-conical member having a shoulder to clamp the inner memory sheet edge against said rim of said member, said members being pivotally mounted about the same axis; power means for rotating said frusto-conical member in either direction about said axis to project said frusto-conical member into and withdraw the same from said recess, respectively, to first and second limiting stop positions, respectively; and motion means including a torque limiter for converting said rotary movements of said frusto-conical member to said axial movements thereof, respectively. 
     
     
       2. The invention as defined in claim 1, wherein said motion means includes a friction device and a spindle, said frusto-conical member being pivotally mounted on said spindle by said friction device on said frame. 
     
     
       3. The invention as defined in claim 1, wherein said frusto-conical member has a cylindrical collar member which is in driving engagement with said power means. 
     
     
       4. The invention as defined in claim 1, wherein sad frusto-conical member is projectable through a memory sheet hole, said frusto-conical member having a face to enter said recess, said frusto-conical member having a periphery, said frusto-conical member having a centering piece on said face for effecting coarse centering, said centering piece having a thickness at least equal to the axial advance movement of said frusto-conical member in the course of one rotation thereof, said centering piece being flush with the said periphery and of said face at least at one point therearound. 
     
     
       5. The invention as defined in claim 4, wherein said centering piece is a round, flat attachment.